Exerpt from the 1934 textbook The Yoga Makaranda. Mayurasana:

This asana must be done before eating (on an empty stomach). Wait a minimum of four hours after eating before practising this asana. This asana should be held from 1 minute up to [a long time] according to the practitioner’s capability. It is good to practise this regularly and to remain in this asana for longer periods during the winter or colder months rather than in the summer.If we make it a habit to practise this asana every day for at least fifteen minutes, we will attain tremendous benefits.

This asana has to be done on the bare ground. There should be no carpet or other spread on the ground.

Technique:

1. Stand upright with the legs together. Jump spread the legs apart so that there may be 12 inches between the feet. Lift the arms, interlace the fingers and turn the palms upwards. Stretch the body and the arms. Inhale.

2. While exhaling, lower the trunk by bending the body at the hips. Keep the arms stretched. When the hands are near the ground, the fingers are freed, the palms turned downwards and placed between the feet firmly on the ground, the finger pointing towards the back and the little fingers touching each other. The legs should be kept stretched and the knees should not be bent. The spine should be kept stretched and as straight as possible.

3. Inhale and lift the head.

4. Exhale, bend the head, spread, the elbows for the passage of the head and place thehead between the knees.

5. Inhale, lift the head and come back to the position in step (3)

6. Take a few deep breaths.

7. While inhaling, jump back with both feet, so that the navel may be above theelbows, when the legs are stretched behind. The legs touch each other, stretched with the toes pointed and the back of the feet resting on the ground. The elbows are placed firmly on the either side of the navel, and the elbows kept as near to each other as possible.

8. Slowly inhale, the inhalation should be only to half the extent that was being done during the previous deep breathing, and move the body forward by about three inches, so that the body assumes the position of a horizontal plank. The legs are to be kept stretched, the knees together and the toes pointed. Head should be raised up.

Note: The final position prescribed above may not be possible in the beginning stages. The feet should be raised only about an inch in the beginning stages of practice, and the height lifted slowly increased as practice advances.

9. Breathe in and breathe out in a regulated manner but with no retention of breath.

10. While inhaling, lower the legs.

11. While inhaling, jump forward and bring the feet on either side of the palms andwhile inhaling life the head to the position in step (3).

12. While exhaling, bend the head, widen the elbows and place the head between the knees.

13. While inhaling, life head and reach the position as in step (3).

14. Lift the trunk and with a jump bring the legs together and reach a position as at thebeginning of the asana.

In this asana, the stomach is compressed, and the lungs are also compressed, and it may appear that regulated breathing in this posture may not be possible.

When Mayurasana has been mastered sufficiently to keep the body steadily horizontal for half a minute, the variation mentioned below-Padma Mayurasana-can be done.